CN112980548B - Method for producing an oleogel capsule and method for producing a vehicle contact part comprising an oleogel capsule - Google Patents

Abstract

The present application relates to a method for preparing an oleogel capsule and a method for manufacturing a vehicle contact part comprising an oleogel capsule. The oleogel capsule includes an oleogel comprising oil and a gelling agent, and at least one surfactant bonded to the oleogel. The vehicle contact member includes a cover layer formed on a surface of the contact member, the cover layer including an oil gel capsule, wherein the oil gel capsule includes an oil gel including oil and a gelling agent, and at least one surfactant bonded to the oil gel.

Description

Method for producing an oleogel capsule and method for producing a vehicle contact part comprising an oleogel capsule

Cross Reference to Related Applications

According to 35 u.s.c. ≡119, the present application claims priority from korean patent application No. 10-2019-0168352 filed in the republic of korean intellectual property office on day 12 and 16 of 2019, the entire contents of which are incorporated herein by reference.

Technical Field

The present application relates to a method for preparing an oleogel capsule and a method for manufacturing a vehicle contact part comprising an oleogel capsule.

Background

A bearing is one of the mechanical elements that constrains relative motion to desired motion and reduces friction between moving parts. Since bearings are equipped with hard chains or balls and are thus susceptible to fatigue fracture, alloy-based bearings (hereinafter referred to as bearing alloys) having excellent wear resistance, corrosion resistance and thermal conductivity and having a shock absorbing function are generally used.

However, the bearing alloy is also inevitably subjected to wear due to continuous friction, which may lead to a drastic decrease in seizure resistance property. Accordingly, various coating materials, i.e., covering materials, for protecting bearing alloys from wear have been developed, and polyamideimide and lubricants are generally used as covering materials.

When developing the covering material, it is necessary to consider that the wear resistance of the bearing may be significantly reduced in the early stage of the vehicle operation, and to lengthen the life of the composite material (bearing alloy and covering material) by preventing additional wear in the early stage of the vehicle operation, i.e., the initial wear stage of the bearing. Therefore, there is still a need for developing a covering material capable of maintaining seizure resistance property even after abrasion occurs in a composite material.

U.S. patent No. 9,982,715 discloses microcapsules as one type of covering material. The microcapsules contain a liquid lubricant in the hard plastic skin and the liquid lubricant may be released to the outside only when the plastic skin is physically damaged. It can be said that the release of the liquid lubricant is independent of the temperature environment of the composite material. In addition, the damaged plastic skin may not only cause engine failure, but also reduce engine efficiency, as the damaged plastic skin may coalesce.

Japanese patent document JP 2013-113371 discloses a lubricant composition that responds to temperature changes. Korean patent document KR 10-0454659 relates to a method for penetrating a lubricant composition including a lubricant and a gelling agent into a pore passage inside a bearing which is a sintered material. However, the high viscosity of the lubricant composition and the limited size of the pores in the bearing have limitations for its application. Furthermore, since there is no disclosure of the lubricant composition as a covering material for bearings, there is a limitation in referring to the lubricant composition as a method of extending the life of the composite material.

Disclosure of Invention

The present application relates to a method for preparing an oleogel capsule and a method for manufacturing a vehicle contact part comprising an oleogel capsule. The embodiments relate to a material for a coating layer formed on a surface of a vehicle contact member such as a bearing alloy.

Embodiments of the present application provide a covering material that is responsive to a temperature environment.

Embodiments of the present application also provide a covering material that does not cause coalescence phenomena even after the oil is released.

Embodiments of the present application may provide a method for preparing an oil gel capsule (oil gel capsule). Embodiments of the present application may include (a) preparing an oleogel by mixing an oil and a gelling agent, and (b) producing at least one oleogel capsule by mixing the oleogel with an aqueous surfactant solution.

Preferably, the oleogel capsule may be produced by surrounding the oleogel with a surfactant.

Preferably, the oleogel in step (b) may be in a liquid state.

Preferably, the oleogel capsule may have a size of 0.1 μm or more and less than 10 μm.

Preferably, the oleogel capsule may have a size of 0.1 μm or more and 1 μm or less.

Preferably, an ultrasonic mill may be used to mix the oil and the gellant.

Preferably, an ultrasonic mill may be used to mix the oleogel and the aqueous surfactant solution.

Preferably, embodiments of the present application may further include (c) drying the aqueous solution.

Preferably, the aqueous solution may be freeze-dried.

Preferably, after step (c) is performed, the oleogel capsules may be collected as oil powder, wherein at least two or more of the oleogel capsules are coalesced.

Embodiments of the present application may provide a method for manufacturing a vehicle contact member comprising an oleogel capsule. Embodiments of the present application may include the above steps (a) - (c), and may include (d) preparing a first organic solution including 2wt% to 10wt% of the oil gel capsule by redispersing the oil powder in an organic solvent, (e) preparing a cover mixed solution by mixing the first organic solution and a second organic solution including 30wt% to 50wt% of the polyamideimide and the additive in a weight ratio of 1:0.5 to 1:2, and (f) coating a surface of the contact member with the cover mixed solution, and then drying the contact member.

Preferably, the cover layer formed by step (f) may have a thickness of 10 μm to 30 μm.

According to the embodiment of the present application, it is possible to provide a covering material capable of responding to a temperature environment and improving abrasion resistance and seizure resistance.

According to the embodiment of the present application, even after releasing the oil, the coalescing phenomenon of the gelling agent and the coalescing phenomenon of the surfactant do not occur.

Drawings

Fig. 1 illustrates a bearing comprising an oil gel capsule according to an embodiment of the present application.

Fig. 2A-2C are confocal fluorescence images of oil gel capsules included in bearings.

Fig. 3 illustrates a process for preparing an oleogel capsule.

Fig. 4A and 4B illustrate the results of measuring the phase transition temperature of the oleogel by DSC according to the weight ratio of 12-HSA.

Fig. 5A and 5B are a series of photographs taken at 25 ℃ after forming an oleogel having a phase transition temperature of about 62 ℃ by mixing engine oil and 2wt% 12-HSA. Fig. 5A is an oleogel without added colorant, and fig. 5B is an oleogel with added colorant. The colorant is added to more clearly show the state of the oleogel.

Fig. 6A and 6B are photographs taken after heating the oleogel of fig. 5A and 5B to 90 ℃.

Fig. 7A and 7B are photographs taken after adding 2wt% PVA aqueous solution to the oleogel of fig. 6A and 6B and mixing.

Fig. 8-10 are confocal fluorescence images of the oil gel capsules in the aqueous solution of fig. 7B.

FIG. 11 illustrates a size distribution of the oleogel capsule in the aqueous solution of FIG. 7A as measured by dynamic light scattering.

Fig. 12A and 12B are photographs taken after freeze-drying the aqueous solution in fig. 7A and 7B.

Fig. 13A and 13B are photographs taken after preparing a first organic solution containing 10wt% oil gel capsules by redispersing the oil powder in fig. 12A and 12B in an organic solvent NMP.

Fig. 14A and 14B are photographs taken after mixing the first organic solution of fig. 13A and 13B and the second organic solution including 50wt% of polyamideimide and additives at a weight ratio of 1:1.

Fig. 15A and 15B are photographs taken after coating the surface of the bearing alloy with the cover mixed solution in fig. 14A and 14B.

Fig. 16 and 17 are graphs illustrating the results of the reciprocating sliding friction test of the steel disk samples of examples 1 to 3 and comparative example 1.

Fig. 18 illustrates the action of the oleogel capsule.

Detailed Description

Hereinafter, embodiments of the present application will be described in detail. However, the present application is not limited or restricted by the exemplary embodiments thereof. The objects and effects of the present application will be naturally understood or apparent from the following description, and are not limited only to the following description. In addition, in the description of the embodiments of the present application, when it is determined that detailed description of known technologies related to the present application does not necessarily obscure the gist of the present application, the detailed description thereof will be omitted.

Figure 1 illustrates a bearing comprising an oleogel capsule. Fig. 2A-2C are confocal fluorescence images of oil gel capsules included in bearings. Referring to fig. 1 and 2A-2C, the bearing 10 may include a back steel (back steel) 100, a bearing alloy 200, and a cover layer 300, and the cover layer 300 may include at least one or more oil gel capsules 310.

The oil gel capsule 310 is a particle including an oil gel 311 and a surfactant 312 surrounding the oil gel 311, and more specifically, the oil gel capsule 310 is a particle including the oil gel 311 and at least one or more surfactants bonded to the oil gel 311. The oil gel 311 refers to oil including the gelling agent 311B, and may include the oil 311A and the gelling agent 311B.

Fig. 3 illustrates a method for manufacturing an oleogel capsule. Referring to fig. 3, a method for preparing an oleogel capsule may include (a) forming an oleogel by mixing oil and a gelling agent, and (b) producing at least one oleogel capsule by mixing the oleogel and an aqueous surfactant solution. Hereinafter, with further reference to fig. 4A-11, steps (a) and (b) will be described in detail.

Step (a): by mixing the oil and the gellant, an oleogel may be formed. The gelling agent may be added to the oil. However, since the specified addition target and addition direction as described above are not required, the oil may also be added to the gelling agent. An ultrasonic mill may be used to mix the oil and gellant for more uniform mixing. The formed oleogel may be in a gel state.

Preferably, the weight ratio of gellant (the weight of gellant based on the total weight of the oil) when mixing the oil and gellant is a weight ratio effective to completely mix the oil with the gel. Also, since the phase transition temperature of the oleogel varies depending on the weight ratio of the gelling agent, the weight ratio of the gelling agent is preferably a weight ratio that effectively maintains the oleogel in a gel state at room temperature, and is preferably a weight ratio that effectively maintains the gel state even in all temperature environments (up to about 60 ℃) that may be experienced before the bearing including the oleogel is mounted on a vehicle.

The phase transition temperature of the oleogel refers to the temperature at which the oleogel in the gel state liquefies into a liquid state or the oleogel in the liquid state gels into an oleogel in the gel state. The oleogel may remain in a gel state at a temperature below the phase transition temperature and may remain in a liquid at a temperature above the phase transition temperature.

According to an exemplary embodiment of the present application, the oil may be engine oil, and the gelling agent may be 12-hydroxyoctadecanoic acid (hereinafter referred to as 12-HSA). The weight ratio of 12-HSA is preferably 1% -10% by weight based on the total weight of the engine oil, and the oleogel may have a phase transition temperature of about 60 ℃ or higher and about 70 ℃ or lower. When less than 1wt% of 12-HSA is mixed with engine oil, a network fiber structure of 12-HSA may not be formed in the engine oil, and thus, an oleogel may not be formed. When more than 10wt% of 12-HSA is mixed with engine oil, the oleogel may reach a saturated state, in which case the amount of increase in the phase transition temperature of the oleogel is reduced due to an increase in the weight ratio of 12-HSA, and the weight of the engine oil is relatively reduced compared to the weight of the gelling agent, so that the lubricating performance of the oleogel or oleogel capsule may be deteriorated. Therefore, 12-HSA is preferably added in an amount of 1wt% to 10wt% based on the total weight of the engine oil. However, the type of the gelling agent and the weight ratio of the gelling agent are not limited thereto.

Fig. 4A and 4B illustrate the results of measuring the phase transition temperature of the oleogel by DSC according to the weight ratio of 12-HSA. Referring to fig. 4A and 4B, it can be confirmed that an oleogel having a phase transition temperature of greater than about 61 ℃ can be formed when 1.5wt% or more of 12-HSA is added.

Fig. 5A and 5B are a series of photographs taken at 25 ℃ after forming an oleogel having a phase transition temperature of about 62 ℃ by mixing engine oil and 2wt% 12-HSA. Fig. 5A is an oleogel without added colorant, and fig. 5B is an oleogel with added colorant. The colorant is added to more clearly show the state of the oleogel. Referring to fig. 5A and 5B, it can be seen that the oleogel exists in a gel state in which there is no fluidity in a temperature environment below a phase transition temperature of about 62 ℃. No fluidity can be seen from the fact that the surface of the oleogel is not parallel to the ground. The gel state of the oleogel more specifically refers to a state in which the oil is formed and maintained while being limited in the network fiber structure of the gelling agent.

Fig. 6A and 6B are photographs taken after heating the oleogel of fig. 5A and 5B to 90 ℃. Referring to fig. 6A and 6B, it can be seen that the oleogel resumes fluidity and exists in a liquid state in a temperature environment higher than the phase transition temperature of about 62 ℃. The fluidity can be seen from the fact that the surface of the oleogel is approximately parallel to the ground. The liquid state of the oleogel more specifically refers to a state in which the network fiber structure of the gelling agent is disintegrated, so that the gelling agent exists in a state dispersed in the oil.

It can be seen that when comparing fig. 6A and 6B with fig. 5A and 5B, the liquid oleogel is more transparent than the gel in the gel state. When the oleogel in fig. 6A and 6B is cooled to 25 ℃, the oleogel may be restored to the oleogel state in fig. 5A and 5B.

Step (b): at least one oleogel capsule may be produced by mixing an oleogel with an aqueous surfactant solution. The oleogel capsule may be produced while the oleogel in the surfactant aqueous solution is surrounded by each surfactant molecule. In one aspect, it can be seen that the oleogel is encapsulated by the surfactant. More specifically, since the oleogel is fat-soluble (hydrophobic) and the surfactant aqueous solution is hydrophilic, an interface can be formed between the surface of the oleogel and the aqueous solution, and the oleogel capsule is produced while the fat-soluble portion of the surfactant faces the oleogel and while the hydrophilic portion of the surfactant faces the aqueous solution.

Preferably, the oleogel capsules may be produced by mixing a liquid oleogel with an aqueous surfactant solution. The oil gel in the gel state may be liquefied in advance and mixed with the surfactant aqueous solution, and after the oil gel in the gel state is added to the surfactant aqueous solution or the surfactant aqueous solution is added to the oil gel in the gel state, the oil gel in the gel state may be liquefied while being mixed by the ultrasonic mill using heat energy emitted from the ultrasonic mill. In any case, it is preferable to use an ultrasonic mill for more uniform mixing.

Since the surfactant is capable of refining the oleogel, a fine oleogel capsule can be produced. Because the oleogel is made fine, the oleogel capsules can be more uniformly dispersed in the cover layer. The oleogel capsule may be formed to have a size of less than 10 μm, which is the average thickness of the cover layer, and which may be 0.1 μm or more and less than 10 μm. Preferably, the oleogel capsule may have a size of 1 μm to 5 μm, and more preferably 1 μm or less.

The surfactant may prevent coalescence of the finely divided oil gel when the coalesced oil gel capsules, hereinafter defined as oil powder, are redispersed in an organic solvent.

According to an exemplary embodiment of the present application, the surfactant may be polyvinyl alcohol (PVA), and 1wt% to 10wt% of PVA aqueous solution may be mixed with the oleogel. Herein, 1wt% to 10wt% means a weight ratio of PVA to an aqueous PVA solution. When a PVA aqueous solution of less than 1wt% is mixed with oil gel, the coalescence phenomenon of the oil gel capsules occurs strongly when the coalesced oil gel capsules defined as oil powder as follows are redispersed in an organic solvent, so that the coalesced oil gel capsules cannot be redispersed. When the PVA aqueous solution exceeding 10wt% is mixed with the oleogel, the oil content in the oleogel capsule is relatively reduced, so that the lubricating properties of the oleogel and the oleogel capsule may be deteriorated. Since the surfactant functions to make the oleogel finer so as to uniformly disperse the oleogel in the cover layer of the oleogel capsule and prevent the oleogel from coalescing, the type of surfactant and the content of the surfactant are not limited thereto, and the surfactant may be selected from anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants. Meanwhile, when the oleogel and the surfactant aqueous solution are mixed, the weight ratio of the oleogel to the surfactant aqueous solution may be 1:2 to 1:10.

Fig. 7A and 7B are photographs taken after adding 2wt% PVA aqueous solution to the oil gel of fig. 6A and 6B and mixing. Referring to fig. 7A and 7B, it can be confirmed that the transparent oil gel in a liquid state before mixing becomes milky white (white color like milk). This means that an emulsion of fine particles in an aqueous solution has been formed, and the fine particles are called oil gel capsules.

Fig. 8-10 are confocal fluorescence images of oil gel capsules in the aqueous solution of fig. 7B. FIG. 11 illustrates a size distribution of the oleogel capsule in the aqueous solution of FIG. 7A as measured by dynamic light scattering. Referring to fig. 8 to 11, it can be confirmed that the oleogel capsule may not have a spherical shape and its size is 1 μm or less. More specifically, the size of the oleogel capsule is 0.1 μm (=100 nm) and 1 μm (=1000 nm).

The method for making the oleogel capsule may further include (c) drying the aqueous solution including at least one or more oleogel capsules. As the aqueous solution including the oil gel capsules is dried, the distance between the oil gel capsules may become small, and coalescence of the oil gel capsules may occur. The fact that the oil gel capsules coalesce does not mean that at least two or more oil gel capsules are integrated into one oil gel capsule, but that the surfactants of the respective oil gel capsules are in physical contact with each other. Agglomerated oil gel capsules have a powdery shape while being sticky like clay, and may have a soft feel like powder. Hereinafter, the coalescence of at least two oil gel capsules is referred to as oil powder. The oil powder may be added to an organic solvent and the coalesced oil gel capsules may be redispersed. The drying in step (c) is preferably carried out using a freeze dryer.

Fig. 12A and 12B are photographs taken after freeze-drying the aqueous solution in fig. 7A and 7B. Referring to fig. 12A and 12B, the oil powder can be confirmed, and it can be said that the oil gel capsule is recovered in the form of powder. One powder of fig. 12A and 12B may have a size that can be distinguished with naked eyes, but since the oil gel capsule prepared through step (B) has a micro unit (sub-micro unit) size, it can be said that one powder is formed by coalescing a plurality of oil gel capsules.

Hereinafter, a process of adding the oil gel capsule manufactured through steps (a) - (c) to the cover layer of the bearing will be described in detail. The steps described below may be referred to as steps (d), (e) and (f).

In step (d), the coalesced oil gel capsules may be redispersed by adding the oil powder to an organic solvent. Agglomerated oil gel capsules may be dispersed as shown in fig. 8-10. However, unlike fig. 8 to 10, both the oleogel and the organic solvent such as N-methyl-2-pyrrolidone (NMP) are fat-soluble, so that an interface may not be formed on the surface of the oleogel, and a part of the surfactant combined with the oleogel may be dispersed in the organic solvent. The organic solution containing 2wt% to 10wt% of the oil powder is referred to as a first organic solution, and it can be said that the first organic solution is an organic solution containing 2wt% to 10wt% of the oil gel capsule. Here, wt% refers to the ratio of the weight of the oleogel capsule to the total weight of the first organic solution.

Fig. 13A and 13B are photographs taken after preparing a first organic solution containing 10wt% oil gel capsules by redispersing the oil powder in fig. 12A and 12B in an organic solvent NMP. Referring to fig. 13A and 13B, it can be seen that coalescence of the oil gel capsules has been eliminated by the translucent color of the first organic solution.

In step (e), a cover mixed solution may be prepared by mixing a first organic solution and a second organic solution comprising 30wt% to 50wt% of polyamideimide and additives in a weight ratio of 1:0.5 to 1:2. Herein, wt% refers to the ratio of the weight of the solid content to the total weight of the second organic solution. The solvent of the second organic solution may be NMP. Fig. 14A and 14B are photographs taken after mixing the first organic solution of fig. 13A and 13B with a second organic solution including 50wt% polyamideimide and additives at a weight ratio of 1:1.

In step (f), the bearing may be dried after the surface of the bearing alloy is coated with the overlay mixture solution. Fig. 15A and 15B are photographs taken after coating the bearing alloy surface with the coating mixture solution in fig. 14A and 14B. The bearings may be dried in one step and may also be dried in two steps to preserve the oleogel capsule. The fully dried bearing may have a cover layer with a thickness of 10 μm-30 μm.

Hereinafter, examples and comparative examples of the embodiment of the present application will be described.

Process for preparing oil gel capsules

After 0.3030g (about 2 wt%) of the gelling agent 12-HSA was added to 15g of engine oil, an oleogel having a phase transition temperature of about 62 ℃ was prepared by mixing the mixture using an ultrasonic mill. 5g of oleogel was liquefied, 75ml of a 2wt% PVA aqueous solution was added thereto, and then the mixture was mixed by using an ultrasonic mill to prepare oleogel capsules. The oil powder is recovered by removing water from an aqueous solution comprising oil gel capsules using a freeze dryer.

Process for producing a coating

Example 1

An NMP solution (first organic solution) comprising 10wt% oil gel capsules was prepared by adding 10g of oil powder to 90g of NMP solvent. After the first organic solution was prepared, the oleogel capsules were uniformly redispersed in NMP solvent using a stirrer. After preparing an NMP solution (second organic solution) including 50wt% polyamideimide and additives including a lubricant, a blanket mixed solution was prepared by mixing 50g of the first organic solution and 50g of the second organic solution. After the surface of the bearing alloy was coated with the overlay mixture solution and dried at 150-200 ℃ for 30 minutes, an overlay layer having a thickness of about 10 μm was prepared by drying the surface of the bearing alloy at 210-240 ℃ for 15 minutes (example 1 is represented by sample 1 in fig. 16 and 17).

Example 2

A coating layer having a thickness of about 20 μm was prepared by coating the surface of the bearing alloy twice with the covering mixed solution in example 1 (example 2 is represented by sample 2 in fig. 16 and 17).

Example 3

A coating layer having a thickness of about 30 μm was prepared by coating the surface of the bearing alloy three times with the cover mixed solution in example 1 (example 3 is represented by sample 3 in fig. 16 and 17).

Comparative example 1

A cover layer of about 10 μm was prepared using only prototype DLA02 (comparative example 1 is represented by DLA02 in fig. 16 and 17).

Fig. 16 and 17 illustrate the results of the steel disk sample reciprocating sliding friction test of examples 1 to 3 and comparative example 1. The test conditions were a dry condition, 10 minutes, 50N load, a reciprocation speed of 5Hz and a reciprocation distance of 10mm stroke. Referring to fig. 16 and 17, it can be seen that in the case of comparative example 1 excluding the oil gel capsule, a continuous increase in friction force and a decrease in contact voltage were observed by repeated friction test, but in the case of examples 1 to 3, the initial friction coefficient and contact voltage were maintained even after 10 minutes passed. That is, it was confirmed that the oil gel capsule can improve the low friction performance and seizure resistance of the bearing.

Fig. 18 illustrates the action of the oleogel capsule in steps (a) - (c). During initial phases of vehicle operation, friction against the bearings may cause wear or cracking of the coating and bearing alloys and localized increases in temperature. The local increase in temperature may transform the oleogel in a gel state into an oleogel in a liquid state, and the oleogel in a liquid state may form a lubricating film at the site of wear or rupture. Therefore, additional friction and wear on the bearing in the wear step can be suppressed at an early stage of the vehicle operation, and the life of the bearing can be prolonged. In addition, the gelling agent may be diluted with an excessive amount of engine oil, and since the gelling agent does not form a network fiber structure at a low concentration, a coalescence phenomenon of the gelling agent does not occur even after releasing the oil. The surfactant is also diluted with engine oil so that coalescence is not possible.

The oleogel capsule may be added to a lubricant, and may further improve the lubricating properties of the lubricant. In addition, with the demand for development of next-generation environmentally friendly vehicles, for example, the advent of high-efficiency engines, the oil gel capsules can also be applied to engines of hybrid vehicles in which the engine friction and wear environment is further deteriorated, electric vehicles operating in a non-lubricated environment, and hydrogen fuel cell vehicles.

While the application has been described in detail with respect to various embodiments and representative examples, those skilled in the art to which the application pertains will appreciate that various modifications may be made in the above-described embodiments and examples without departing from the scope of the application. Therefore, the scope of the present application should not be limited to the above-described embodiments and examples, but should be determined not only by the claims described below, but also by all changes or modifications that come within the meaning of the claims and their equivalents.

Claims (16)

1. An oleogel capsule comprising:

an oleogel comprising oil and a gelling agent; and

a surfactant bound to the oleogel;

wherein the oil is an engine oil, the gellant is 12-hydroxyoctadecanoic acid, and the 12-hydroxyoctadecanoic acid is present in an amount of 1wt% to 10wt%, based on the total weight of the engine oil;

wherein the oleogel has a phase transition temperature of 60 ℃ to 70 ℃.

2. The oleogel capsule of claim 1, wherein the oleogel is in a gel state at a temperature less than the phase transition temperature.

3. The oleogel capsule of claim 1, wherein the oleogel is in a liquid state at a temperature greater than the phase transition temperature.

4. The oleogel capsule of claim 1, wherein the oleogel capsule has a size of 0.1-10 μιη.

5. The oleogel capsule of claim 1, wherein the oleogel capsule has a size of 0.1-1 μιη.

6. The oleogel capsule of claim 1, wherein the surfactant is polyvinyl alcohol.

7. A toner comprising a plurality of the oleogel capsules of claim 1, wherein the oleogel capsules are coalesced.

8. A vehicle contact member, the contact member comprising:

a cover layer formed on a surface of the contact member, the cover layer comprising an oil gel capsule, wherein the oil gel capsule comprises:

an oleogel comprising oil and a gelling agent; and

at least one surfactant bound to the oleogel;

wherein the oil is an engine oil, the gellant is 12-hydroxyoctadecanoic acid,

and the content of the 12-hydroxyoctadecanoic acid is 1wt% to 10wt% based on the total weight of the engine oil;

wherein the oleogel has a phase transition temperature of 60 ℃ to 70 ℃.

9. The contact member of claim 8, wherein the cover layer has a thickness of 10-30 μιη.

10. The contact member of claim 8, wherein the cover layer comprises an organic solution comprising the oil gel capsule.

11. The contact member of claim 10, wherein the cover layer is configured to be coated on a surface of the contact member, and the contact member is configured to be dried after the cover layer is coated thereon.

12. The contact member of claim 10, wherein the oleogel is in a gel state at a temperature less than a phase transition temperature, and wherein the oleogel is in a liquid state at a temperature greater than the phase transition temperature.

13. The contact member of claim 10, wherein the surfactant is polyvinyl alcohol.

14. A method for manufacturing a vehicle contact member, the method comprising:

preparing an oleogel by mixing an oil and a gelling agent;

producing a plurality of oleogel capsules by mixing the oleogel with an aqueous surfactant solution to form an aqueous solution;

recovering oil powder by drying the oleogel capsule and the aqueous solution;

preparing a first organic solution comprising 2wt% to 10wt% of the oleogel capsule by redispersing the oil powder in an organic solvent;

preparing a cover mixed solution by mixing the first organic solution and a second organic solution comprising 30wt% to 50wt% of polyamideimide and additives in a weight ratio of 1:0.5 to 1:2;

coating the surface of the contact member with the coating mixture solution; and

drying the contact member;

wherein the oil is an engine oil, the gellant is 12-hydroxyoctadecanoic acid, and the 12-hydroxyoctadecanoic acid is present in an amount of 1wt% to 10wt%, based on the total weight of the engine oil;

wherein the oleogel has a phase transition temperature of 60 ℃ to 70 ℃.

15. The method of claim 14, wherein the drying comprises freeze-drying.

16. The method of claim 14, wherein the surfactant is polyvinyl alcohol.